I have 2 80 Gb HDD's with a RAID 0 motherboard configuration (Intel Z77, fakeRAID) with a 100 Gb partition running Windows 7 and a 60 Gb partition where I would like to install Ubuntu 12.10. However, even though the installer seems to correctly detect the RAID 0 array, GRUB2 is not installed and the computer boots into Windows normally. The same thing does not happen when installing Fedora 17. The installer (Anaconda) also detects the disk array, but GRUB2 installation is successful. What exactly are the differences between Ubiquity and Anaconda? And is there a way to correctly install GRUB2 in a fakeRAID system, since there are no alternative Ubuntu CDs?

2 Answers
2

You need to put GRUB2 outside of the array, or it will not be seen and booted.

When you create your arrays from the Intel utility, you need to leave a couple of hundred MB, on each drive, outside of the created arrays and put GRUB onto one of these, during the installation process. You can do this by creating a ~500MB array, then your ~100GB and ~60GB arrays and then going back and deleting your ~500MB array. This will leave you the necessary space at the start of the drive for your bootloader. You will then need to use Advanced Partitioning during installation and mount this as /boot.

It's been a while since I did this, but I think that this should work from the Live CD. Make sure that you have dmraid installed, and I'd advise doing most of your partitioning through gparted before running the installer. Format one of these two partitions to ext2 to mount your /boot on this, use the ~60GB (/dev/mapper/isw...) volume to create your / (root) (ext4), and swap (swap) partitions and then mount them in the Advanced Partitioning bit of the Ubuntu installer.

Make sure that you select the low-down-on-the-list, individual entries for your (/dev/mapper/isw...) volumes for mounting during installation.

It does not seem to work, GRUB still boots into rescue mode, claiming error: no such partition. There is an option during the Ubuntu installation, "Device for bootloader installation" that I left as default, with /dev/sda . On the other hand, what does Fedora's installer does differently that manages to correctly install GRUB?
–
João AndréDec 20 '12 at 16:13

I've found an effective way to do this. As Rich.T wrote, the /boot should be a separate partition at the start of the disk array. However, Ubiquity still won't correctly install the bootloader, so a workaround is to boot with an image of Ubuntu Secure Remix and run the Boot-Repair tool, following each procedure. An alternative way could be to either install the whole OS from the Secure Remix CD or to install Boot-Repair in the normal Ubuntu Live CD, however I have not tested it so I cannot guarantee they would work.

NOTE: It is also required that both Ubuntu CDs boot into non-UEFI mode, otherwise it will not work.